The field of robotics has become sufficiently sophisticated so that it is now possible to use robotic drilling in aircraft assembly operations. A common assembly operation in this field of manufacture involves attachment of an exterior member to an underlying support structure or other member. Conventional metal fasteners are used to make this kind of attachment, with the fastener being installed in and extending through coaxial bores in the pieces to be connected.
Generally, it is desirable that the installed fastener's head be flush with the outside surface of the exterior member. This requires the bore in the outside surface to have a countersink for receiving the fastener's head. Robotic drilling has been useful as a means for automatically and quickly drilling straight bores, but has proven problematical when attempting to drill bores with a countersink all in a single drilling operation. As a practical matter, this is best done in two stages, with a straight bore first being drilled and a countersink later being made.
It is important the countersink be normalized relative to the exterior member's outside surface so that the fastener's head may be installed substantially flush therewith. The purpose of the present invention, therefore, is to provide an end-effector assembly, for use in connection with robotic countersink drilling, that carrier a motor and cutting tool for countersinking a bore, and which acts to place the cutting tool in normality relative to the outside surface of the exterior member.